CHICAGO , Illinois -LRB- CNN -RRB- -- Chicago authorities asked Illinois Gov. Rod Blagojevich to issue a disaster declaration after rainfall Saturday in the Windy City broke a single-day record that had stood for more than two decades .

Chicago received more than 6 inches of rain Saturday , breaking a 1987 record .

The deluge flooded streets and stranded residents in their homes . Officials worked to rescue people Sunday as the city grappled with another day of drenching .

O'Hare International Airport recorded 6.64 inches of rain Saturday -- breaking the all-time record of 6.49 inches set in 1987 , according to the National Weather Service . Records have been kept since 1871 .

By 4:30 a.m. CT on Sunday , emergency management and law enforcement officials were reporting widespread flooding across much of northern Illinois and extreme northwest Indiana , with rainfall totals of 4 to 7 inches in certain areas , the weather service said .

Commissioner John Spatz of Chicago 's Department of Water Management said the north branch of the Chicago River `` rose quickly and began to flow down the 5000 block of North Monticello , '' causing flooding northward and southward . Watch how Chicago flooded before Ike 's rains arrived ''

In the worst-hit area , Albany Park , about 340 homes were in danger . About 40 residents were evacuated -- some of them by boat -- and taken to a shelter .

About 90 billion gallons of water fell on the city 's water district , authorities said . More than 20 water department crews were out , and widespread sandbagging operations were under way .

Spatz said the city 's sewer system was still `` working well . ''

City officials said that , in general , things were under control .

Saturday 's pounding rain was not related to Hurricane Ike . Remnants of Tropical Storm Lowell , which had come in from the Pacific , got caught up with a cold front , sending a wave of moisture into the region .

But on Sunday , as the remnants of Ike -- by then a tropical depression -- worked their way farther into the country 's heartland , heavy rain was expected over much of the region , including Illinois .

On Sunday morning , the National Hurricane Center said flood and flash-flood watches were in effect for much of the state . But police reported no major incidents .

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Records kept since 1871 say Saturday 's rain marks worst in more than century

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Heavy rain more related to Tropical Storm Lowell in Pacific than Gulf Coast 's Ike

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Commissioner : Chicago River flowed `` down the 5000 block of North Monticello ''

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Authorities say 90 billion gallons of water fell on the city 's water district